The following location must be found to enable cheat mode. After the game begins, move to the right until reaching a location with a teddy bear. Then, face the wall and press Circle to jump in that direction. If done correctly, you will hear a muted sound. Now move forward and walk in the next room just to the right of this location, which leads down into a small room. Press Circle to access a platform. Use this platform to reach a playroom and activate cheat mode. The following codes may now be enabled:

Invincibility

While playing the game, press X(4), Triangle, Circle, X, Square on controller two.

All weapons

While playing the game, press Circle(3), Triangle(2), X(2), Square on controller two.

Level select

While playing the game, press Triangle(3), Square(3), X(2), Circle on controller two.